Not from a moral but a practical matter:
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Iraq had engaged in two wars of conquest against its neighbors in the last few decades. So you had more regional support for the invasion than for current regional support for the invasion of Venezuela. Turkey did refuse to use its country as a staging ground to invade Iraq, but several Persian Gulf states hosted coalition troops.
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The USA attempted to make its case diplomatically before invading. Sure, the case for the invasion of Iraq was built on lies, but at least a case was being made diplomatically. Also, the USA was citing UN resolutions as a justification for war even if it was incorrectly doing so; that hasn't happened in the taking of Maduro.
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There was a coalition of the willing that was invading Iraq, not a solitary country. The USA wasn't going alone and was apply to rely on multiple countries approving this action even if it didn't have UN approval.
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Bush wasn't threatening to invade several allies before invading Iraq. While there was dubious legality to the invasion of Afghanistan as it was a non-state actor which attacked the USA, the USA was at least and to cite self defense in is invasion.
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The world's opinion of the USA was a lot higher at the time.
Spock is going to have to give back that valuable whale vomit.